Microflora on bean seeds (Phaseolus vulgaris L.).


  • José B. Membreño Universidad de Puerto Rico, Mayagüez.
  • Mildred Zapata Universidad de Puerto Rico, Mayagüez.
  • James Beaver Universidad de Puerto Rico, Mayagüez.
  • Rusty Smith Estación de Investigación de Agricultura Tropical, Mayagüez




The bacterial microflora present and its relationship with Xanthomonas campestris pv. phaseoli (Xcp) were studied in bean seeds, on 118 genotypes coming from VIDAC - 98, INTA - Nicaragua, TARS - USDA and Isabela - P.R. Five isolation methods were used: seed decontaminated with sodium hypochlorite, seed treated with refrigerated nutrient broth for one hour, dispersion of 0.1 ml of suspension of seeds between solid, liquid sowing of 1 ml suspension and seed in nutritious, agitated broth and refrigerated by 24 hours. One hundred and four yellow colonies from 41 genotypes were isolated. Thirty-six colonies were positive KOH (Gram negative), 68 negative (Gram positive) and 34 were starch hydrolyzers. The yellow colonies were nonpathogenic under greenhouse conditions. These were identified with the BIOLOG system as: Pantoea agglomerans (25), Xanthomonas campestris (2), Enterobacter agglomerans (2), Sphingomonas paucimobilis (2), Pseudomonas fluorescens and Flavimonas oryzihabitans. In addition, the genotypes carried colonies with other pigmentations. Antagonistic colonies were identified with deoxyribonuclease activity and antibiosis to Xcp. Of these, 15 colonies inhibited Xcp significantly. The fungi were identified as: Rhizoctonia solani, Penicillium spp., Fusarium spp., Aspergillus flavus, Rhizopus nigricans and Macrophomina phaseolina in 52.9% of the total evaluated genotypes.


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AGGOUR, A. R. 1987. Genetics of and breeding for resistance to Xanthomonas campestris pv. phaseoli (Smith) in beans (Phaseolus vulgaris L.). Ph.D. Diss., University of Nebraska, USA. 141 p.

BARNETT, H. L, HUNTER, B. B. 1998. Illustrated genera of imperfect fungi (Fourth edition). The American Phytopathological Society, St. Paul, Minnesota. 218 p.

BEEBE, S. E., PASTOR, M. A. 1991. Breeding for disease resistance. In: Van Schoonhoven, A., Voysest, O. eds. Common beans: research for crop improvement. Commwealth Agricultural Bureau CAB International, Wallingford, United Kingdom. p. 561-610

CAFATI, C. R., SAETTLER, A. W. 1980. Transmission of Xanthomonas phaseoli in seed of resistant and susceptible Phaseolus vulgaris genotypes. Phytopathology 70(7):638-640.

LEYNA, H., COYNE, D. 1985. The effect of inoculation methods, pathogenic variability and inoculum concentrations on reactions and genetics of resistance to isolates of Xanthomonas campestris pv. phaseoli in leaves and pods of dry beans (Phaseolus vulgaris L.). Bean Improvement Cooperative 28:70-71.

LÓPEZ, M., FERNÁNDEZ, F., SCHOONHOVEN, A. V. 1985. Frijol: Investigación y producción. CIAT, Colombia. 417 p.

PASTOR, M. A., SCHWARTZ, Y H. 1994. Problemas de producci ón del frijol en los trópicos. Segunda Edición. CIAT, Colombia. 734 p.

SAETTLER, A. W. 1989. Common bacterial blight. In: Schwartz, H., Pastor, M. eds. Bean production problems in the tropics. 2nd. Ed. CIAT, Colombia. p.261-283.

SAETTLER, A. W., PERRY, S. K. 1972. Seed transmited bacterial diseases in Michigan Navy (pea) beans Phaseolus vulgaris. Plant Dis. Rep. 56:(5): 378-381.

SCHAAD, N. W. 1994. Laboratory guide for identification of plant pathogenic bacteria. 2da Ed. APS PRESS, St. Paul, Minnesota, 158 p.

SCHWARTZ, H. F., GÁLVEZ, G. E. 1981. Bean production and pest constraints in Latin America. In: H. F. Schwartz and G. E. Gálvez (eds.). Bean production problems in the tropics. CIAT, p. 3-4.

SCHWARTZ, H. F., PASTOR, M. A. 1989. Bean production problems in the tropics, 2nd Ed. CIAT, Colombia. 726 p.

SUTTON, M. D., WALLEN, V. R. 1970. Epidemiological and ecological relations of Xanthomonas phaseoli and x phaseoli var fuscan on bean in Southwestern Ontario, 1961- 1968. Canadian J. Bot. 48:1329-1334.

ZAPATA, M., FREYTAG, G. F., WILKINSON, R. 1985. Evaluation for bacterial blight resistance in beans. Phytopathology 75(9):1032-1039.

How to Cite

Membreño, J. B., Zapata, M., Beaver, J., & Smith, R. (2006). Microflora on bean seeds (Phaseolus vulgaris L.). Agronomía Mesoamericana, 12(2), 135–139. https://doi.org/10.15517/am.v12i2.17224